Why can’t a woman be more like a man? Henry Higgins demands to know in "My Fair Lady." These days, labor economists are asking the opposite question: Why can't a man be more like a woman?

The decline of traditionally male blue-collar work like manufacturing has left many men adrift. There are growth industries, such as health care, where some of these men could get work. But they don’t seem to be taking advantages of the splendid opportunities to become home health care aides or day care workers. In part that’s because many of these jobs don't start out paying as well as the manufacturing jobs these men have lost or had hoped to gain. But in part it seems to be because the work isn't … well … manly enough.

“It’s not a skill mismatch, but an identity mismatch,” economist Lawrence Katz told the New York Times. “It’s not that they couldn’t become a health worker, it’s that people have backward views of what their identity is.”

This seems unnecessarily dismissive. If Katz lost his job as an economist, and had to take one changing the diapers of elderly patients, I’ve no doubt that he would find this emotionally difficult, but I wouldn’t say that this is because his preferences for his current occupation are “backward.” The patient-care work is necessary, and should be honored. It’s also, let’s be honest, much less pleasant than sitting in an office and writing about what other people should do with their working lives.

Moreover, people invest a lot in building up a professional identity, which helps make the work more bearable (and, by giving people pride in what they do, probably ensures that the work is better done). Suddenly abandoning something that has constituted a major part of who you are, and taking a job at the bottom of a new field, is not any easier for a machinist or a coal miner than it would be for a professional.

Besides, before we start blaming identity, we should also at least be willing to ask about capacity: How many men have the predisposition to be good at these sorts of “nurturing” professions?

As a female journalist who writes mostly about traditionally “male areas” such as economics and business, I should perhaps be expected to endorse a “blank slate” theory of male and female gender roles, where the preference for certain kinds of activities is driven by sexist socialization and discrimination, not innate ability. The problem is that this doesn’t necessarily match up with the evidence. Human children show gender-driven preferences for toys, as can be attested by those faultlessly progressive parents who have seen their boys turn their hands into a gun while their daughters make a doll out of an ear of corn. These preferences show up even in children too young to have gotten much socialization; they turn up even in rhesus monkeys, as males show a marked preference for wheeled toys over soft plush animals. I certainly believe that human society has a lot of sexist hangovers from its past. I draw the line at believing that this hangover is influencing rhesus monkey infants.

So I think we have to take seriously the possibility that many men aren’t just avoiding the caring professions because they look down on the things that ladies do, but because many of them actually don’t have the aptitude and patience for nurturing and caregiving work that some women do.

Sex differences are a distribution, not a hard, bright line. For example, the women’s world record in the hundred-meter dash is slower than the U.S. high school boys' record. Men on average are faster than women. But the women at the top of the distribution -- those Olympians -- are still faster than most men. It would be absurd to say that a woman can’t run the hundred meter in 11 seconds, just because most women can’t. It would be equally absurd to say that men are not, on average, faster than women.

So it’s possible that the distribution of nurturing traits is skewed enough that fewer men will be good at the difficult and emotionally taxing job of providing intimate care for sick and needy people. While there are plenty of health care jobs that don’t require so much direct human interaction, they tend to require more training. And the ability to sit in a classroom and absorb material from a textbook is also a human trait that is unevenly and unfairly distributed. It’s not that no men can succeed in transitioning from old-style “manly” jobs to the pink-collar professions, but that fewer men may be able to do so than we’d like to think.

This of course raises an uncomfortable question: What should men do if they have a hard time making that transition? Those manufacturing jobs are not coming back, even if Donald Trump shuts down trade with China, because a lot of them haven’t been lost to foreign competition but to competition from robots residing right here in the good ol’ U.S. of A. Unless we start a bunch of inefficient old-fashioned factories that exist solely for the purpose of providing people work, we’re going to need some sort of Plan B for many would-be workers.

I wish I had a better idea what Plan B was. But the solution that economists and policy wonks have been pushing for decades -- more education and transition into service work -- is manifestly not working for a lot of people. Indeed, it sounds a lot like professional identity politics: The experts say that the solution to all problems is for everyone to be more like them. It may not be possible for an average man to turn himself into an average woman to suit the needs of the job market.

If we can’t build a job market that offers opportunity and satisfaction for diverse abilities and identities, we may see a lot more convulsions of popular dissatisfaction like the one we witnessed last November.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Megan McArdle is a Bloomberg View columnist. She wrote for the Daily Beast, Newsweek, the Atlantic and the Economist and founded the blog Asymmetrical Information. She is the author of "“The Up Side of Down: Why Failing Well Is the Key to Success.”

If we can’t build a job market that offers opportunity and satisfaction for diverse abilities and identities, we may see a lot more convulsions of popular dissatisfaction like the one we witnessed last November.